Tuesday, July 16, 2013

Finally an Unvented Washer/Dryer that Works Pretty Good

The status quo method of drying clothes inside a house is a lousy method. If you use an electric dryer, you are buying expensive heat to raise the temperature of the dryer airstream, and then you blow that air directly outside. Whenever you blow air out of the house, it must be replaced with unconditioned air from outside. So using your dryer causes you buy about twice as much heat as the dryer actually uses. The hole in the side of your house for the dryer vent also tends to make the house leak more air than if you didn't have that hole.

"Heat pump dryers" are the most efficient way to dry clothes, but we can't buy 'em in the US yet.

"Condensing dryers" are currently the best alternative we have. They dry the air by condensing the water vapor out of the air rather than blowing it outside.

LG and others make "combo" units that combine a washer and condensing dryer into the same appliance. Not only does that save a lot of expensive real estate inside your house, the user doesn't have to transfer the clothes from the washer to the dryer. Put your clothes in at night, wake up to clean and dry clothes. Cool.

I've been following the development of these appliances for 10 years, and found that they were unacceptable because they never got the clothes dry enough.

LG has a new model that seems to work. The online reviews are by far the best I've seen for any washer/dryer.

So your new house can be designed without a dryer vent, which is a win-win.

4 comments:

I have been wondering for a while why dryers are electric, would it not be possible to use hot water(low grade energy), in place of electric (highly refined energy). I am imagining something like refrigerator coils wrapped around the drum instead of resistor wires. I am curious why this is not done? Is it inefficient? Seems like this would save money when using solar hot water, even gas should be cheaper than electric per unit of energy. Perhaps it could even be used in conjunction with the aforementioned refrigerator coils? This would also remove one of the larger electric loads for an off grid setup.

Using hot water, especially solar-heated hot water sounds nice in theory. The trouble is that most SHW systems operate between 90 and 150 deg F, which isn't hot enough to evaporate the water on the clothes. Great for domestic uses like washing dishes, showers, etc., but just not hot enough to dry clothes. Maybe you could use a combination of SHW and something else, but that gets kinda complicated.

About Me

He received a BS in Engineering Physics from the Colorado School of Mines in 1977. During the country's first Solar Era, he received an MS in Mechanical Engineering and Solar Technology from CSU (1979) After involvement in hundreds of solar thermal systems in the early 80's, he received several product design patents. The focus of this blog is low and zero energy home design and construction for Denver.